Officials said the sick traveler who was diagnosed while in Massachusetts also spent time in New Hampshire, going to the Flatbread Company restaurant in Portsmouth on April 20 between 3 p.m. and 6 p.m.

Anyone who was at the restaurant during those hours should monitor their symptoms, officials said. Symptoms of the measles virus include high fever, cough, runny nose and conjunctivitis prior to development of a body rash. Anyone who feels sick should contact their healthcare provider, officials said.

Officials believe the restaurant is the only known public exposure site in the state.

There are no known cases related to the situation, officials said, adding that the state has a 96 percent measles vaccination rate in school-age children.

“We are still in the early stages of investigating, but we do not anticipate a large outbreak because of the high vaccination rate of people in the state,” said Dr. Benjamin Chan, state epidemiologist. “But it is possible there could be cases in New Hampshire related to travel by this individual. It is a good time for people to check their own vaccination status if they were born in or after 1957.”

According to state health officials, measles is caused by a virus that is passed from person to person through the air when an infected person sneezes, coughs or talks. The measles virus can remain in the air for up to two hours after an infected person visits and leaves an area.

The infected person also shopped at the outlet mall in Kittery, Maine on April 20. Officials said the man shopped in stores including The Kittery Trading Post, Calvin Klein, Ralph Lauren and J. Crew.

The incubation period for measles is typically 10 to 14 days, but it can be as long as 21 days.